Tony

Here are the results of the Panasonic 4 x 18650 cells (3400 mah) On my Xtar charger, I get very close to the stated capacity which is appreciated (thanks to Panasonic). I got a comfortable 7 hours operating time (Max GAIN and 10uS) with a just audible THRESHOLD and VOLUME The pack started out at 16.3v (down from the 16.6v fully charged as I had used it for about 30 minutes) After 1 hour the pack read 15.7v (a drop of 0.6v) After 2 hours the pack read 15.20v (a drop of 0.5v) After 3 hours the pack read 14.70v (a drop of 0.5v) After 4 hours the pack read 14.20v (a drop of 0.5v) After 5 hours the pack read 13.65v (a drop of 0.55v) After 6 hours the pack read 12.55v (a drop of 1.1v) After 6.5 hours the pack read 11.80v (a drop of 0.75v) Each battery tested and found to be about 2.95v to 3.00v In summary, the pack will give about 7 hours of run time before the pack reaches to 12v mark (or 3v per cell). This is a generous built in safety margin as the low voltage cutoff built into each cell is 2.5v. Some people believe not to discharge below 3v. As you can see, the first 5 hours discharge is very linear but accelerates for the final 2 hours. As expected, the depth drops off slightly but only noticeable/measurable at around the 5 hour mark. This pack will be perfect for in the water as 7 hours deep digging in the water is plenty for me. If on the beach then a battery swap after 5 hours is easy enough. Tony.

I thought I'd copy this from my other thread which was buried down on the second page.......is this okay Steve as I don't want to duplicate if unnecessary? "Just got back from the beach....in one word.........awesome. Some observations; It is the deepest detector I have ever used on the beach (in the past 25 years) by running the higher voltage pack. It is the first time I have ever detected (with any detector, including the Minelab PI's) my gold wedding ring at a measured/buried 18" deep. The US nickel can be heard at 16" in buried wet sand...but with GB OFF. With GB ON it drops to 12"-13" ! My machine is much deeper with GB OFF across all targets.....the rock solid threshold with GB OFF is unbelievable with no loss of sensitivity. Even with the coil swept through shallow salt water at max gain and 10us......it is so smooth. I don't know how White's have done it....maybe a new batch of the latest flux capacitors...... I tried with GB on but in clean white sand, there was no perfect GB....it was close but just a slight positive signal as the coil was lowered to the ground...but the depth loss was significant with GB on and slight falsing with higher GAIN. None of this is a problem with GB OFF." Tony PS.......on the real deepies (edge of detectability), there is often a one, two and three way signal but not a four way signal if swept from left,right and up and down.

I am currently monitoring the run time on my 4 x 18650 pack. If I can get around 6-7 hours before the overall pack drops below 12v then I am happy. The Panasonic 18650 cells have the inbuilt low voltage cutoff at 2.5v per cell or 10v overall but I plan to build in more safety margin.....more details soon. Back to your last post.....I was trying to work out how to connect directly to the detector's contact pins but it is not easy. One way is to try different size female spade connectors (or similar) and with very long thin nosed pliars, reach down and gently push the (pre-wired +-) connectors on...........fiddly but workable with the right tool.

Just got back from the beach....in one word.........awesome. Some observations; It is the deepest detector I have ever used on the beach (in the past 25 years) by running the higher voltage pack. It is the first time I have ever detected (with any detector, including the Minelab PI's) my gold wedding ring at a measured/buried 18" deep. The US nickel can be heard at 16" in buried wet sand...but with GB OFF. With GB ON it drops to 12"-13" ! My machine is much deeper with GB OFF across all targets.....the rock solid threshold with GB OFF is unbelievable with no loss of sensitivity. Even with the coil swept through shallow salt water at max gain and 10us......it is so smooth. I don't know how White's have done it....maybe a new batch of the latest flux capacitors...... I tried with GB on but in clean white sand, there was no perfect GB....it was close but just a slight positive signal as the coil was lowered to the ground...but the depth loss was significant with GB on and slight falsing with higher GAIN. None of this is a problem with GB OFF. Tony

Some good information here....I used to run the Beach Hunter 300 so I am used to the positive buoyancy. I use an "S" shaft when in the water as I find it easier to leverage more downward force if needed. On the beach itself, I will carry a spare battery pack (sealed in ziplock bag) but in the water, the 4 x 18650 (3300mah measured) should give me 6-7 hours run time. .............now, if you'll excuse me, I'm off to the beach ! Tony

Is this designed to be an external battery pack because I can't figure out how that will fit inside the TDIBH battery compartment ? Tony

I am guessing not all in series....maybe a 4 series and two parallel.....AKA....... 4S2P......?

I am still "wowed" by the rock solid threshold with GB Off....but it is sensitive enough to let you hear "microscopic" changes when something really deep is there.......? For the record.......the small plastic tabs that need to be removed from inside the battery compartment lie where the back end of the two outer batteries sit. Tony.

Well I sat down and re-visited the 4 x 18650 batteries for the TDI Beach Hunter and managed a successful battery boost.....It's a snug fit but went in better than expected. Now someone probably has another version but here is my Ghetto version ! I needed to remove most of the White's battery holder to reduce the overall height otherwise the 18650 holder would sit on the floor of the White's holder. All that's really needed is the end part to make the electrical contact. The two outer batteries are quite secure inside the detector as they snug up against the battery compartment housing. 1. Cut down AA White's battery holder 2. Trimmed down 18650 battery holder 3. Removal of two small plastic tabs from the "roof" of the detector's battery compartment (easy and very neat) 4. Bit of hot glue to bring the two holders together but doesn't need to be super strong. 5. Soldering of 18650 leads to contacts on the White's battery holder And for the record.........the depth increase on my gold ring is a solid 1.5" to 2" over the standard 12v pack. Range has jumped from 14" to 16" with GB off and everything else at max.

Thanks Steve for those links.......I try to avoid creating new threads without duplication !

I have discovered that 4 x 18650 cells cannot fit into the battery compartment without Dremmeling that area and that is something I won't do. The battery compartment has 4 or 5 internal ribs that run down the whole length and this is what prevents those batteries from fitting. It looks like it has to be a maximum of 3 x 18650 cells which of course won't get us to the fabled higher voltage and better depth of detection..........anyone know what a realistic depth increase would be from that extra 3.7v cell? Thanks, Tony

Okay, back from the beach and did some basic tests.... Nice clean white sandy beach so it would GB "the same" across the whole pot setting. No GB needed but a noticeable depth increase when GB engaged. Now, the GB "hole" changes when testing a gold and platinum ring so I really don't know where to set the GB to maximise coverage and limit the "hole"....and then with the pulse delay skewing results even further. Am I reading into this too much..................seriously thinking of keeping GB off unless it is really needed for those rare black sand spots. Hmmmmmmmmmmmmmmmmm.........?

Tom and Steve.......appreciate the feedback which all makes sense to me. Maybe it is more prudent to run as a straight PI (GB off) if no GB is actually needed. Some more experimenting is needed but at least I know what the issue is. Thanks again, Tony

My TDIBH got here door to door from the USA in 6 days which is great....thanks again to Gerry at Gerry's Detector's ! I did some basic tests on my back lawn (which is devoid of any metallic targets to at least a metre). I did notice that no GB was needed which is what I would expect but interestingly if the GB was left at "4", the detector would barely detect my gold ring. As soon as the GB was turned higher or lower, then the ring was detected at great distance. I know I can run with no GB (straight PI) but the depth was slightly improved with GB engaged. I am wondering that when I hit the beaches, which down here are generally mineral/black sand free, where should I leave the GB if it's not required? I will most likely bury a target and dial in the GB (assuming it's not actually needed for a proper GB) which gives the best response but I am very wary of a setting that might not see the target ! I am new to the TDI SL platform so any tips is much appreciated. Thanks, Tony

Well that is some good news.......mine is due this Friday so I will put it through some beach tests this weekend. Thanks for the update, Tony

Please keep us updated if they get back to you with a diagnosis. Can I ask what battery you were running at the time (please feel to PM me on this matter ?) Thanks, Tony

That's not what I wanted to hear.......hope my unit is okay as it is a 20,000 mile round trip !

Great news....mine is inbound from the USA !! Tony PS....Thanks to Gerry

What's the retail price on these in the UK? Thanks, Tony

Thanks Gerry for that piece of potentially good news. I have just bookmarked your Webpage and if things do work out, then you will be my first choice for anything I need from the USA. Thanks, Tony

I shall have a good look when I go down to my local electronics store. I have also seen mini alliagtor clips that have an adjustable screw that provides extra security. There are also those female spade style connectors that could possibly be used...just find the right size and maybe very lightly crimp if necessary. ..........just need the detector first ! Hoping they will be for sale soon as they are available for pre-order by a few dealers in the USA.

My plan is to use the 4x18650 holder (secured with 3M velcro to the inside of the battery compartment) and then connect directly to the detector's battery contact points via insulated mini alligator clips. It might be a bit tricky to reach down there to the contact points but it is possible. Failing that, then still use the 4x18650 battery holder (electrically connected within the standard AA holder)....and then slide on in. Standard AA holder will need some modding so the 18650 pack can fit in okay (height clearance). We shall see......?

Dear Mr White....? Us Aussies love White's detectors and now that we no longer have an AUTHORISED White's dealer here in Australia, can you please relax the conditions on your White's dealers in the USA to allow them to sell directly to us............pleeeeezzzzz.....? Yes we have some general 3rd party detector sellers but not that long ago, one of them went bankrupt whilst still selling detectors that many people never got ! Thanks for your consideration... Tony

Tom, If we were to provide suitable new coils to White's for fitting then would our warranty remain intact. Would we get a credit on the stock dual field coil? Thanks, Tony

If only there was a way to connect/solder a generic power lead to the actual internal detector's battery contacts and then use whatever custom NiMH or Li-Ion battery pack that will fit inside the battery area. Thoughts on using a high quality silver based epoxy/adhesive to electrically connect a power lead to the detector's battery contacts ?